Flow intermitter



Nov. 25, 1941.

A. BOYNTON v 2,263,565

FLOW INTERMITTER Filed Nov. 2a, 1938 4 Shets-Sheet 1 ALEXA N DER BOYNTON,

ATTORNEYSL' Nov. 25, 1941.

A. BMOYNTQN 2,263,565

FLOW INTERMITTER Filed Nov. 28, 1938 4 Sheets-Sheet 2 ALEXANDER BOYNTON,

., BY E 'gj g ATTOIQNEYS.

Nov. 25, 1941.

A. BOYNTON 2,263,565

FLow INTERMITTER Filed Nov. 28, 1938 4 Sheets-Sheet 3 J so 66 5o I 'l2o36A 55 Fig. 10.

ALEXANDER BOYNTON, INVENTOR,

A TTORNEYS.

, Nov. 25, 1941. A. BOYNTON- 2,263,565

FLOW INTERMITTER ALEXANDER BOYNTON,

I/NE/vgoR,- BY Z ATTORNEYS factory production if flowed and, the flowtubing, as from the annular space between the pressure Patented Nov. 251941 UNITED STATE s PATENT OFFICE FLOW INTERMITTER Alexander Boynton,San Antonio, Tex. Application November 28, 1938, Serial No. 242,773

16 Claims.

My invention relates to flowing liquid from wells, particularly oilfrom. deep wells, by means of intermittent flow using compressed air orgas as the lifting force. The flowing operation coin- Some wells, hereintermed high pressure wells, will yield their production satisfactorilyif air or gas at high pressure is applied above the liquid inthe-annular space between the well casing and the flow tubing. Otherwells, herein termed low pressure wells, will not yield satisbycompressed air or gas unless the same is prevented from exerting itsforce upon the producing formations of the wells. In such a well, astring of pressure tubing having the flow tubing within it and a bottomseal between them may be employed to con-. tain the pressure fluid, andthus prevent it from retarding inflow ofwell liquid. Such installationsare shown in my Patents Nos. 1,968,633, 2,006,909, 2,010,135, 2,042,583.

This invention will function equally well whether the pressure fluid tooperate it comes from the annular space between the well casing inhighpressure wells, or

tubing and the flow tubing, as in low 'pressure wells.

This specification will describe and the draw? lngs will illustrate thedevice as installed upon a high pressure well employing pressure fluidfrom the annular space between the'well casing and the flow tubing tooperate the-same. It is understood that the installation may be alsomade upon low pressure wells. by using pressure fluid to operate thedevice froni th'eannular space between the pressure; j bing and the flowtubing; There is; a so-caIIedFc -itical point inthepres sure, that isthe pressure at which a; wellwlll' yield its productionby use of theleast amount of pressure nui This relation between the amount ofwellliquid pri'lduc'e'dv and the ,"amount of gas used to produce it 'iscommonlyrei'erred to as, the gas-oil ratio} device may be adjusted tclopen at any pressure and to close at ton which is moved any lesserpressure, allowing some difference, of course, for friction which inthis mechanism, is slight.

One of the objects of this invention is to provide automatic means forflowing oil wells at as near as possible to the critical point, asdefined in the preceding paragraph. If, for example, the critical pointis 300 pounds, this device may be set to open the valve in the flowtubing to initiate flow at 320 pounds, and to close at 280 pounds- 20pounds on either side of the critical point.

A further object of the invention is to regulate the pressure atwhich-gas wells orstorage reservoirs of gas 'or liquids can be made todischarge gas or liquids into a line or other receptacle at apredetermined relatively low pressure existing in the line orreceptacle, and to cut off the discharge into same at a relativelyhigher pressure obtaining therein by slightly changing the installationplan as will be later explained.

Another object of this invention is to provide means for closing valvesto prevent wastage from bursted pipe lines.

, Other objects of this invention are to provide means to propel a solidor liquid body' of material by intermittently discharging hi h pressureair or other fluid substance behind them.

\ In accomplishing the foregoing objects, a cased well, having aflowtubing extending to proximate the bottom thereof and with a hermeticseal provided between them proximatethe ground sur-- face, has a valvein casing head witha shell having oppositely inclined spiral openings onopposite sides fitting over the valve stem with a transverse pin throughit engaged with the spiral openings of the shell, the'shell actuatingthe valve by means of a pisto open the valve by pressure exterior of theflow.

later moved to close it by weight or spring after the pressureinuthewell, has decreased to a predetermined value below that whichobtainedv when the valve opened.. t

Many other than .herein enumerated can be, made of this ventive skill toapply it, as be more apparent man an examination of the accompanyingdraw-- ings in which:

g, I lean eleyation of the devil and I section 01 th upper end well. v

Fig. 2 is a plan view or the device shown'inm. a is a partial sectionalelevation of the agvice-shownin l 'ig.l.'" 1

Flags is'a "section en the flow tubing above the.

tubing within the well and.

invention without requirin in--'-" the'lineH, m. s.

actuating finger in Figs. 1 and 3.

Fig. 7 is a section on the line 1-1, Fig. 3.

r Fig. 8 is a partial sectional elevation of the 1,

first modified form of the invention.

Fig. 9 is a section on the line 99, Fig. 8.

Fig. 10 is a quarter turn partial section and partial elevation of aportion of the device shown in Fig. 8.

Fig. 11 is a partial sectional elevation of the second modified form ofthe invention.

Fig. 12 is a section on the line l2l2, Figs. 11 and 13.

Fig. 13 is a quarter turn elevation of a portion of the invention asshown in Fig. 11, showing a partial section of the valve operatingmechanism.

Identical characters of reference refer to similar parts throughout theseveral views.

The first form of the invention is shown in Fig. 1, in which well casingI has a flow tubing 2 extending central thereof to proximate the bottomof the well. The nipple 2a is welded at 2' to plate and is threadedlyjoined with nipple 2b by coupling 2d.

The casing head assembly composed of base 3, cap 4, plate 5, and packing6 afiord well known means for accomplishing a hermetic seal between thewell casing and flow tubing proximate ground surface G. Bull plug 1 maybe used to close the unused opening of the casing head.

' Upon the'upper end of nipple 2b, valve 8 is uireadedly engaged. Thebent nipple 2c engaged upon the other end of the valve has connectionwith a line leading to a tank or other storage.

Valve stem 3a, rotatable in one direction to open valve 8 and to closeit by'rotation in the opposite direction, is secured within extension 9by a pin Ill. The lower end of extension 9, slidable within shell l2 andthrough internal flange l3b, has pin H tightly engaged within it. Theends of this pin protrude equally on opposite sides of extension 9 so asto be flush with the outside of shell l2. Over the ends of pin H,rollers Ha have free rotatable engagement and have slight clearancewithin the slots l2a of shell I2 which is firmly secured upon itscarrier I 6 by.

nut I5 which looks the finger I 4 between it and carrier l6. Slot 16aserves to allow shell 12 to be moved away from nipple 2b as may benecessary to cause it to register with the valve stem extension 9 if alarger valve than the one shown at 9 should be employed. A hood I 3 hasthreaded engagement. upon the upper end of shell I 2, the unthreadedportion having slight clearance over the other portion of the shell inorder to hold house the mechanism. The sloping internal circularshoulder 13a oi the internal flange I 3b engages the upper end of shell12 so as to force the mating threads infirm contact with each other,thereby preventing distortion oi! the slotted shell as is apparent inFigs. 3, 8 and 11.

It will be noted that slots |2a (Fig. 3) are oppositely inclined andpositioned exactly opposite each other in the shell l2 so that pin IIand rollers Ila will impart rotation to valve stem extension 9 as theshell 12 is moved upward or downward.

Cylinder bracket 36, having bolts 39 rigidly engaging teeth 36a upon thenipple 2b, supports cylinder 35 to which it is locked in a fixedposition by nut 31. Bracket 36 and nipple 11, re-

spectively, provide means for supporting the mechanism and holding itparallel with nipple 2b, as shown in Fig. 1.

Nipple I1 threadedly connected within an opening in the casing head,stop cook or valve l8, nipple l9, elbow 26, nipple 20, T 2|, nipple 25,elbow 26a, nipple 21, union 28, nipple 29, and lubricator shell base 36,all threadedly joined together, afford a hermetically sealed tubularcommunication between the annular space S within the casing and theinterior of lubricator shell 32, base 30 and shell 3| being hermeticallyjoined together by weld 30a. Central of, and extending downward from theupper end of shell 3| is a cylindrical extension 31c (Figs. 3 and 10)having threaded engagement with cylinder 35 within which piston isfreely movable.

The latch spacer bolts 66, secured upon bracket 36 and upon latchhousing holder 54 by nuts 61,

serve to support latch housing holder 54 which receives through acentral opening the lower threaded extension 5la of latch housing 5|secured upon the holder 54 by latch lock cap 52. The upper latch housingcover 59, closed at its upper end by cap 65, is threadedly engaged overthe upper end of latch housing 5| and secured in proper position by lockring 60.

Rocker arms 13 are hinged upon arms 36b of I bracket 36 by bolt 14 andhinged upon prongs 68a of the weight lever 68 by bolts 15. Bolt 68 has aclose fit through piston 40 and the member I6 and has a free fit throughthe prongs 68a, thus providing a fulcrum for the lever 68. Extension rod69 is threadedly engaged with the member 68, the engagement beingsecured by lock nut 10.

Weight 1| is engaged over the other end of rod 69 by threads adapted, toallow the weight to be moved inward or outward to exert more or lessforce upon piston 40, as will be later explained. Lock nut 12 obviouslyserves to secure the weight 1| in a fixed position.

Over the lower end extension 40a of the piston, cups 4| are fitted andspaced apart by cup spacer 42, nut 43 serving to lock them in positionas shown in Fig. 3. The nut 43 is of such length as will not allow theend cup to strike the landing below. The tubular extension 32a holds thebase 36 spaced apart from the lower end of shell 32, a hermetic closurebetween base 30 and inner shell 32 being provided by threads and weld,

, vents possible leakage of fluid past 'the external the rollers withinthe slots 12a and otherwise threads on lower end of cylinder 35.

Pressure fluid communication between the lower end of cylinder 35 andthe annular space S within the well is provided through opening 31d, thespace interior of shell 32, the openings 320, the annular space 32d, theopenings 32b, the nipple 29 appearing in Fig. 3, and the lowerconnections shown in Fig. 1. The pressure gauge 24, having communicationwith the pressure fluid within the T 2|, via valve 23 and bushing 22,obviously indicates the operating pressures.

Within the shell 32 is placed a liquid lubricant that will freely passthrough the opening 3ld, the level of which lubricant is shown at 32'.Plug 33 and packing 34 within boss 3lb provides means for replenishingthe lubricant and producing a hermetic seal.

' actuatethe valve 5.

travel should be accurately adjusted to, land shaft 50 on. plate 59a assoon as the valve is open, and

over piston 40. The cap may be locked in position to produce propercompression of the spring by lock ring 45. The balls 51 are adapted tobecome engaged with a portion of reduced diameter 40b of the piston whenthe piston is in its lower position as shown in Fig. 3.

Latch housing contains another latch assembly consisting of ball floor55, balls 51a, ball roof 56, the latter being slidable within thehousing, and spring 58, free all around. This latch engages the turneddown portion 50a-of shaft 50 spring rider 6|. Spring compression nut 64may,

therefore, be raised'or lowered to cause proper compression of spring 58upon ball roof 55 as appears in Fig. 3..

It will be understood that the ball roof and ball floor of each latchare formed adjacent to the balls with arcuate surfaces adapted to urgethe latch balls inwardlyas is apparent in Figs. 3, 8 and 10. It willalso be understood that piston 40 and shaft 50 are freely movablethrough all associated parts in their indicated path of travel exceptthrough shell carrier IE to which piston 40 is fastened by bolt 68'. v

The chamber 59b may be filled with a lubricant which will cushion theupward stroke of piston 40 by the lubricant being forced through theopening of restricted diameter 59d in plate section 59a by latchshaft50. The opening 651: provides air circulation in and out ofthechamber 59c. Baille tube 65', closed proximate its upper end andabove the closure having a perforated tubular portion 65", prevents thelubricant from wasting through the opening 65a as it is forced underpressure by shaft 50 through the opening 59d. Packing 53.,prevents thelubricant from escaping downward. I

The piston travel is determined at its upper end bythe engagement ofshaft 50 upon plate section 59a. screwing the cover 59 upwardor downwardand looking it in correct position with ring 60 provides the necessarystroke to operate the valve 8. Manifestly, the assembly must bepositioned by U bolts 39 and bracket 36 so that valve 8 will be closedwhen the piston is at the lower end of its travel as shown in Fig. 3.

The oppositely inclined slots lZa are of such pitch andleng'th as willactuate valve 8 so as to open it on the up-stroke of shell l2 and closeit on the down stroke. The vertical ends l2b and I20 of the slotsprovidethat the-piston travel may bemore than enough to actuatethe. valvewithout imparting unnecessary strain upon the valve. The verticalportions |2b and 120 may, however, be omitted and the slots I20. may becompression upon spring 58 that the weight H will quickly drop to thedotted. position shown in Fig. 1 when this latch is sprung.

The weight and position of member H on rod 69 manifestly governs thepressure at which the mechanism will operate. Moving the weight outwardincreases this pressure, and vice versa, as

is apparent. The rod 69 should preferably be approximately horizontalwhen the piston is midway of its stroke.

In explaining the operation, it will be assumed: That valve I 8 (Fig. 1)is closed with gas at a pressure of 320 pounds (all pressures being persquare inch) confined within the annular space S; that weight 1| is inthe lower position and will resist rising by 300 pounds pressure underthe piston; that the lower latch is adjusted to hold .against 20 poundsunder the piston independent of weight 'II; and that the upper latchwill hold by the equivalent of 20pounds pressure under the piston.

Valve I8 is now opened. Pressure builds up on top of the oil or otherlubricant having its level at 32' within shell 32 (Fig. 3). Thispressure transmits through opening 3ld to the piston and cups. At 320pounds pressure the lower latch is sprung- The piston rises until shaftstrikes plate 59a. The shell 12 is at the same time raised from itslower position and opens valve 8 (Fig. 1). The lubricant in shell 32follows the piston, lowering the lubricant level in shell 32 to thehorizon 32" (Fig. 10), thus affording lubrication for the cups ll intheir return movement. The pressure fluid in the annular space S forcesthe well liquid out through the flow tubing. When thepressure drops inspace S to 280 pounds the upper latch is sprung by weight II and thepiston returns to the position shown in Fig. 3, restoring the oil levelto the horizon 32'. This completes the operating cycle. The lower endextension llla of the piston partly closes the passage 3ld slightlybefore the piston reaches its lowermost position longer and have morepitch than is required to Insuch case the piston The upper and therebyfurther aids said comparatively small passage to further cushion thimpact, Manifestly, the annular spaces may be supplied with pressurefluid from an outside source by means of a connection replacing the,bull plug 1.

In the foregoing example, the grip or freeze of the cups against thecylinder wall was not vtaken into-account; because in this constructionthe piston should beof comparatively. small diameter, 2' being ample forthe installation upon an oil well as illustrated. Whatever the force ofthis freeze may be,will aid the lower latch and impede the upper latch.Both latches can readily be adjusted accordingly.

If the well will not how at the pressures available, aerating devicesmay bev installed at intervals in the'flow tubing, Such devices aredescribed in my Patents Nos. 1,470,053, 1,517,611,

A counter, such as shown at 16, many types thereof being manufactured,may be engaged upon the nipple 21) by clamp 16b, secured by clamp bolt160. The counter actuator 16a is adapted to 'be engaged by the finger l4proximate the extremeupper end of the valve opening upward stroke-ofpiston III. for the obvious purpose of recording the number ofeach valveopening or flowing operation.

The first modified form of the inventionis shown in Figs. 8, 9, and 10.In this modificatioii a coiled spring I8 is substituted for weight II inthe first form. Uv bolts 39 serve to secure the bracket 36A upon nipple2b in proper position to actuate valve 8, as was explained in connectionwith Figs. 1 and 3. Bracket 36A, having openings registering withsimilar openings of latch housing holder 54A, space these members apartby means of bolts 66 extending through the openings and secured by nuts61. Arms of spiral shell carrier or crosshead IBA, registering withsimilar arms of spring base 19, are spaced apart by bolts 80 and nuts80a, these bolts passing through shell carrier 16A as appears in Fig.10. The coiled spring I8, free over nipple 29A, is engaged betweenlubricator shell base 30 and spring base 19, slidable over nipple 29A.Nipple 29A (Figs. 8 and 10) is longer than nipple 29 in Fig. 3 butotherwise the same. Set screw 11 secures the shell carrier ISA uponpiston 40A which operates the same as piston 40 in Fig. 3, with which itis identical except that it is somewhat longer and has no'transverseopening for the bolt 68' as in Fig. 3.

All other parts are the same and operate the same as was described forthe first form of the invention. It is apparent that the spring 18 willbe compressed when the piston moves upward; this compressed springfunctions to oppose the upward movement of the piston 40A in the lowerposition and-to urge it downward from its upper position in the samemanner as weight 1| functions in the preceding form of the invention.

In order that this spring will not build up too much resistance duringthe upward ,stroke of the piston, and corollarily that it will .notlose,

too much force during the downward stroke of the piston, it isimportant. that the free length of the spring should be comparativelygreat and that it be installed under'considerable compression. If thepistonstroke is 4", the spring should preferably have approximately 4feet free length and be installed under approximately 2 feet ofcompression. The above is especially true if small difl'erence betweenthe pressures at which valve 8 will open and close is desired.Adjustments of the springcompression may be made by turning lower nuts80a upward or downward as is apparent. central opening through it andslidable over the nipple 29A could be substituted for the spring I8 ifsufficient space be provided between the weight and shell base 30 toallow for proper travel of the shaft 50.

The second modified form of the invention is shown in Figs. 11, 12 and13, wherein spring 18', somewhat differently installed, serves the samepurpose as spring 18 in Figs. 8 and 10. Shell carrier IBB has a twopronged portion within which the lower threaded extension of shellmember I2 is engaged as in the preceding forms. The other end of shellcarrier 16B is formed into an arm having an enlarged circularportionwhich receives through a central vertical opening the latch shaft50A, somewhat longer than the shaft 50 in the other forms of theinvention, but otherwise the same.

A slotted ring 8| with its slots receiving the arm of the shell carrierISB on either side of .its enlarged circular portion rests upon thecircular portion to form a base for spring 18'. The lower end of springadjuster guide pipe 82 has slots 82a with clearanceover the arm of shellcarrier I6B on either side of its enlarged portion, and the lower end ofpipe 82 has slight clearance within Manifestly, a weight having a.

the spring base 8| so that pipe 82 is vertically movable as can be seenin Figs. 11, 12 and 13. Spring 18' has free clearance over pipe 82 andmay have its compression adjusted by nut 88 locked by nut 83, both nutshaving threaded engagement over the upper end of pipe 82. Latch lock cap52A, otherwise the same as lock cap 52 in the preceding forms, hastongue like extensions 52Aa which engage with mating slots within theupper end .of pipe 82, co-acting with slots 82a over the arm of shellcarrier IGB. in order to prevent rotation of the shell carrier IGB dueto the rotary thrust transmitted by shell l2 as its spiral slots causevalve actuation. Cylinder bracket 363, having no extensions or boltconnections as had the corresponding part in Figs. 1 and 3, and 36A inFigs. 8 and 10, serves only to support the cylinder 35. Cylinder bracket363', secured upon nipple 20 by U bolts 39a, serves as an upper supportfor the assembly corresponding to members 54 and 54A respectively in thepreceding forms. Piston 40A is the same in all respects as the pistonemployed in the first modified form except that it is somewhat shorter.To avoid needless repetition,.all parts bearing the same referencecharacters, being substantially the same in construction and purposethroughout all forms of the invention, are discussed with reference tothe first form only.

If, by way of illustrating other uses of this invention, it should bedesired to augment the supply of gas discharged from a reservoir into apipe line, for example, and hold the pressure in the line constantbetween a predetermined high' p and low value, the mechanism, hereinshown and described, may be installed to=actuate a valve 8 such asshown, the high pressure or intake end 01' the valve being toward thereservoir and the low pressure and discharging into the pipe line. Insuch installation the valve must open at a predetermined low pressureunder the piston 48 and close at a predetermined high pressure under it,this being the reverse order of pressures from that hereinbeforedescribed. To accomplish such result, it is merely necessary to reversethe direction of oppositely inclined slots IZa.

It will be understood that the foregoing draw-.

ings and specifications are illustrative, and are not intended to limitthe construction or uses of this invention, which may be greatly variedwithin its contemplated scope and p poses.

I claim: v

1. A flow control for wells having a casing and tubing, a valve tocontrol the discharge of producedfiuid from said tubing, and means tocontrol the operation of said valve including a differentially pressureactuated mechanism wherein the force to open is a source of fluid underpressure and the force to close is mechanical in combination with meansfor causing the opening and closing movements of said valve to bequickly completed.

2. A flow controlfor wells having-a casing and tubing, a valve tocontrol the discharge 01 produced fluid from said tubing, and means tocontrol the operation of said valve including a differentially pressureactuated mechanism wherein the force to open is a source of fluid underpressure and the force to close is mechanical, said pressures beingopposed to each other so that when said fluid pressure drops below apredetermined value said mechanical pressure will close the valve, incombination with latching means for causing the opening and closingmovements of said valve to be quickly completed.

3. A flow control for wells having a casing and tubing, a valve tocontrol the discharge of produced fluid from said tubing, and means tocontrol the operation of said valve including a differentially pressureactuated mechanism wherein the force to open is a source of fluid underpressure and the force to close is mechanical, said:

means including a fluid pressure connection to said casing, a pistonwithin a cylinder, and means for causing the opening and closingmovements of said valve to be responsive to the movements of saidpiston. s

4. A flow control for wells having a casing and tubing, a valve tocontrol the discharge oi control the operation of said valve including adifferentially pressure actuated mechanism wherein the force to open isa source of fluid under pressure and the force to close is mechanical,said pressures being opposed to each other so that when said fluid forcedrops below a predetermined value said mechanical pressure will closethe valve, said means including a weight upon one end of a fulcrumedlever to create said mechanical force, the other end of said lever beinghinged upon a rocker arm.

5. A flow control for wells having a casing and tubing, a valve tocontrol the discharge of produced fluid from said tubing, and means tocontrol the operation of said valve including a differentially pressureactuated mechanism wherein the force to open is a source of fluid underpressure and the force to close is mechanical, said forces being opposedto each other so that when said fluid pressure decreases below apredetermined value said mechanical force will close the valve, by meansincluding a spring to create the mechanical force.

6. A flow control for wells having a casing and tubing, a valve tocontrol the discharge of produced fluid from said tubing, and means tocontrol the operation of said valve including a differentially pressureactuated mechanism wherein the force to open is a source of fluid underpressure and the force to close is mechanical, said forces being opposedto each other so that when said fluid pressure drops below apredetermined value said mechanical force will close the valve, by meansincluding a spring to create the mechanical force, in combination withlatching means to cause said force to be applied suddenly.

I '7. A flow control for wells having a casing and tubing, a valve tocontrol the discharge of produced fluid from said tubing, and means tocontrolthe operation of said valve including a differentially pressureactuated mechanism wherein the force to open is a source of fluid underpresproduced fluid from said tubing, and means ing and valve, pressurefluid to move said piston sure and the pressure to close is mechanical,

said forces being opposed to each other so that when said fluid pressuredrops below a predetermined value said mechanical force will close thevalve, by means including a spring to create the mechanical pressuredisposed with latching means to cause said force to be applied suddenly,and means for cushioning the impact of said differentially operatedmechanism when it opens and closes said valve.

8. A flow intermitter for wells'having a casing and tubing therein,sealing means between said casing and tubing proximately above saidcasing, an annular space within said casing, a valve in said tubingabove said sealing means, a conduit connected to said sealing means andhaving communication withsaid annular space,

a cylinder communicating with said conduit, a piston slidable in saidcylinder and having an extension outward thereof, means, for lubricatingsaid piston. means for opening and closing said valve, said means beingoperable by said piston; a shell surrounding said piston extension abovesaid cylinder, a spring loaded latch assembly within said shell,-saidlatch being to force balls inwardly into engagement with said piston; anannular recess around said piston, said recess being for latchingengagement with said balls when said piston is in its lowermostposition; a latch housing surrounding said piston above said flrst latchand containing another spring loaded latch assembly having other ballsadapted to move into latching engagement within another recess aroundsaid piston when the same is in its uppermost position, a dashpotsecured above and independent of said piston to limit its upstroke andto cushion the impact thereof, meansfor securing said piston andextension thereof upon said tubing and in spaced relation to said tubingand valve, pressure fluid to move said piston in one direction to opensaid valve at a predetermined value of said fluid, and a weight to movesaid piston in the other direction to close'said valve at apredetermined different value of said fluid.

9. A flow intermitter for wells having a casing and tubing therein,sealing means between said casing and tubing proximately above saidcasing, an annular space within said casing,'a valve ,in said tubingabove said sealing means, a conduit connected to said sealing means andhaving communication with said annular space, a cylinder communicatingwith said conduit, a piston slidable in said cylinder and having anextension outward thereof, means for lubricating said piston, means foropening and closing said valve, said means being operable by saidpiston; a shell surrounding said piston extension above said cylinder, aspring loaded latch assembly within said shell,said latch being to forceballs inwardly into engagement with said piston; an annular recessaround said piston, said recess being for latching engagement with saidballs when said piston is in its lowermost position; a latch housingsurrounding saidpiston above said first latch and containing anotherspring loaded latchassembly having other balls adapted to move intolatching engagement -within another recess around said piston when thesame is in its uppermost position, a dashpot secured above andindependent of said piston to limit its upstroke and to cushion theimpact thereof, means for securing said piston and extension thereofupon said tubing and in spaced relation to said tubin one direction toopen said valve at a predetermined value of said fluid, and a spring tomove said piston in the other direction to close said valve at apredetermined difierent value of said 10. A flow intermitterfor wellshaving a casing and tubing therein, sealing means between said casingand tubing proximately abovesaid casing, a space for fluid within saidcasing, a valve in said tubing exterior of said casing, a conduit havingcommunication with said space, a cylinder communicating with saidconduit, a piston slidable in said cylinder and having an extensionoutward thereof, means for lubricating said piston, means for openingand closing said valve, said means being operable by said piston; ashell surrounding said piston extension beyond said cylinder, a springloaded latch assembly within said shell, said latch being to force ballsinwardly into engagement with said piston; an annular recess around saidpiston, said recessbeing for latching engagement with said balls whensaid piston is in its lowermost position, means for securing said pistonand extension thereof upon said tubing and in spaced relation to saidtubing and valve, pressure fluid to move said piston in one direction toopen said valve at a predetermined value of said fluid, and means tomove said piston in the other direction to close said valve at apredetermined different value of said fluid.

11. A flow intermitter for wells having a casing and tubing therein,sealing means between said casing and tubing proximately above saidcasing, a space for fluid within said casing, a valve in said tubingexterior of said sealing means, a tubular conduit having communicationwith said space, a cylinder communicating with said conduit, a pistonslidable in said cylinder and having an extension outward thereof, meansfor lubricating said piston, means for opening and closing said valve,said means being operable by said piston; pressure fluid to move saidpiston in one direction to open said valve at a predetermined value ofsaid fluid, and a Spring to move said piston in the other direction toclose said valve at a predetermined different value of said fluid.

12. In a flow intermitter for wells, the combination of a casing andtubing, sealing means between said casing and tubing exterior of saidcasing, a space for fluid within said casing, a valve in said tubingexterior of said sealing means, a tubular conduit having communicationwith said sealing means and with said space, a

reservoir connected to said conduit, a shell within said reservoir, saidshell having side and bottom clearance with said reservoir; openings forpressure fluid proximate the upper end of said shell, a lubricant withinsaid shell, a cylinder secured upon said reservoir, a piston slidablewithin said cylinder and having an extension beyond the same, means forsecuring said piston and extension thereof upon said tubing and inspaced relation to said tubing and valve, and means for opening andclosing said valve, said means being controlled by said pistonresponsive to the differential force exerted thereon from said an- 7111.113,! space.

13. In a flow intermitter for wells, a valve opening and closing meansconsisting. of a shaft pin secured transversely through said shaft andhaving ends extending therefrom, a shell having oppositely disposedspiral slots engageable over the ends 01' said pins, said shell beinglongitudinally movable over said shaft to impart such limited rotationto said shaft when said shell is moved telescopically over same apredetermined distance in one direction and to impart similarly limitedrotation thereto in the other direction when said shell has equalmovement over said shaft in the opposite direction.

14. In a flow intermitter for wells, a valve opening and closing meansconsisting of a shaft adapted to open a valve'by limited rotation in onedirection and to close said valve by similarly limited rotation in theother direction, a pin secured transversely through said shaft andhaving ends extending therefrom, a shell having oppositely disposedspiral slots engageable over the ends of said pins, said shell beinglongitudinally movable over said shaft to impart such limited rotationto said shaft when said shell is moved telescopically over same apredetermined distance in one direction and to impart similarly limitedrotation thereto in the other direction when said shell has equalmovement over said shaft in the opposite direction, and a mechanicalcounter for numerically recording the operations of said valves.

15. In a flow intermitter for wells, the combination of a cylinderhaving communication with the interior of a well, a piston in saidcylinder, a valve on a tube having communication with the interior ofsaid well, means for securing said piston relative to said valve, meansfor operating said valve by movement of said piston, tubular meansconnecting said cylinder to the interior of said well, pressure fluid insaid well 'to move said piston in one direction and to operate saidvalve in one direction, and pressure means acting upon said piston toforce it in the reverse direction to operate said valves in the reversedirection when said pressure fluid force changes to anotherpredetermined value.

16. In a flow intermitter for wells, the combination of a cylinderhaving communication with the interior of a well, a piston in saidcylinder, a valve on a tube having communication with the interior ofsaid well, means for securing said piston relative to said valve, meansfor operating said valve by movement of said piston, tubular meansconnecting said cylinder to the interior of said well, pressure fluid insaid well to move said piston in one direction and to operate said valvein one direction, pressure means .acting upon said piston to force it inthe reverse direction to operate said valve in the reverse directionwhen said pressure fluid force changes to another predetermined value, asecond valve and a pressure gauge in said tubular means, and amechanical counter to numerically record the operations of said firstvalve, said counter being operable by means attached to said piston.

ALEXANDER BOYNT'ON.

